This is normal. In the novel almost all the rather cute seggsy scenes are not fully explained/shown. So it's to be expected that's the same for the manhwa.
But in this chap the seggs is not that important. It's more about the feels. Taes disappointment with just s** and no feelings and how Ilay is making fun of him and tells him he likes/love him. Just to be surprised by Taes kiss and totally gets confused and can't stop the kissing. 😂 it's such a cute scene.